Traffic & Safety

4- to 3-lane conversion myths

4 Lane Example

Myth: Drivers will be diverted from the area

False. For the majority of 4- to 3-lane conversions, traffic volumes remain about the same through the corridor. In addition, 3-lane roads are generally more efficient than 4-lane roads because vehicles no longer need to stop in the thru lane to make left turns.

Myth: Economic development will be stifled

False. Converting to a 3-lane road can positively impact property values and businesses. When converting a 4-lane road to a 3-lane road, additional features can be added in the unused space, such as parking and/or bicycle lanes. These features can improve livability and transform the corridor into one people want to drive on versus drive through. Additional parking can provide a benefit to businesses and the center left turn lane improves access.

Myth: Traffic will back up

False. Studies have consistently shown that, for roads with less than 20,000 vehicles per day, 4- to 3-lane conversions will not worsen congestion. In fact, operations and safety improve on a 3-lane road because left turns are shifted into the center turn lane, allowing traffic to flow more freely in the thru lanes.

Myth: Large vehicles like farm equipment cannot be accommodated

False. Impacts to large vehicles such as farm equipment are minimal. Because the width of the pavement does not change, large vehicles can continue to use the road as they have in the past. Tractors and combines that are wider than one lane can extend into the center lane, as needed, for travel through town.

Myth:Emergency response times will increase

False. Contrary to beliefs, a 4- to 3-lane conversion does not increase emergency response times. In fact, response times usually improve because emergency vehicles can utilize the center turn lane when responding to an incident. This avoids bottlenecks that can occur on 4-lane roads when drivers in the middle lanes try to move over for the emergency vehicle, but can't.



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